Hydrodynamic analysis of flow patterns and estimation of retention time for a polluted reservoir

Abstract

Abstract

This paper presents a numerical prediction of the flow patterns in a polluted reservoir to supply the fire control water and to process water to an oil refinery. A biological treatment for improving water quality started in 1995. Although the treatment was successful in reducing organic load and bad odour, it was suspected that the locations of the inlet and outlets in the reservoir were possible causes for a short cut in the flow, which might greatly reduce the efficiency of the biological treatment. A numerical investigation to simulate and predict the fluid motion was carried out with the aim of providing quantitatively remedial approaches to perfect the biological treatment process, especially for future working conditions of increased pumping flowrate. The numerical analysis predicted the appearance of a flow short cut in the reservoir with the consequential reduction in its retention time; simulation has shown that this negative characteristic can be eliminated if the inlet and the outlets are relocated.